/* 让容器的宽度和高度充满全屏 */
html,body{
    width: 100%;
    height: 100%;
}
body{
    background-color: pink;
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-items: center;
}
*{
    padding: 0;
    margin: 0;
}
.heart{
    width: 200px;
    height: 200px;
    background-color: red;
    position: relative;
    transform: rotate(45deg);
    animation: heartbit 1s alternate infinite;
    box-shadow: 0 0 30px red;
}
.heart::before{
    content: "";
    width: 200px;
    height: 100px;
    background-color: red;
    position: absolute;
    left: 0;
    top: -99px;
    border-radius: 100px 100px 0 0;
    box-shadow: 0 0 30px red;
}
.heart::after{
    content: "";
    width: 100px;
    height: 200px;
    background-color: red;
    position: absolute;
    top: 0;
    left: -99px;
    border-radius: 100px 0 0 100px;
    box-shadow: 0 0 30px red;
}

@keyframes heartbit{
    0%{
        transform: rotate(45deg) scale(0.6);
    }
    100%{
        transform: rotate(45deg) scale(1.4);
    }
}